Flow-controlled valve



March 31, 1942. H, THOMPSON 2,278,001

FLOW-CONTROLLED VALVE Filed May 8," 1939 INVENTOR PARKE H. THOMPSON ATTORNEY Patented Mar. 31, 1942 rm orgies- FLOW-CONTROLLED VALVE Parke H. Thompson, Millville, N. J., assignor f thirty-five per cent to Russell Maguire, New

York, N. Y.,

Application May 8, 1939,'Serial No. 272,375

24 Claims.

This invention relates generally to valves and,

more particularly, to a certain new and useful improvement in flow-controlled valves adapted particularly for use in connection with refrigerating systems and the like. 7

My invention has for its primary objects the provisionof a control valve of the type stated, which is simple in construction and economical in operation and maintenance, which may be readily designed as a complete unitary structure, which is uniquely responsive to a function of the system which it controls so as to achieve and maintain an extremely high erhciency in the system regardless of design or load conditions, which is automatically compensated for over-' travel, which is adapted to extract any liquefied portions of the returning fluids from the system with which it is connected and reintroduce such separated liquid into the system with the incoming supply of fluid over which control is being maintainedand which is highly efficient in the performance of its intended functions.

And with the above and other objects in view, my invention resides in the novel features of form, construction, arrangement, and combination of parts presently describedand pointed out in the claims.

In the accompanying drawing:

Figure l is a vertical sectional view of a fluidflow control valve constructed in accordance with and embodying my present invention;

Figures 2 and 3.are transversesectional views of ,the'valve, taken approximately along the linesv 2-2 and 3-:3, respectively, Figure 1;.

Figure 4.is a schematic View of a refrigerating system incorporating ,a control .valve of my invention; and

Figure 5 is a fragmentary sectional view. of an adjustable leak port which may be usedin connection with the present invention.

Referring now more in detail and by reference characters tothe drawing, A designates, in a preferred form, a control valve of my present-invention. Such valve includes a-cylindrical preferably metallic shell I open at its upper endiand there provided with an annular mounting flange 2 having a plurality of internally threaded apertures 3.

At its lower end, the shell I is welded orotherwise hermetically sealed to .an end plate :4 centrally ,providedwith an internally threaded ap-- erture 'ziforadjustably receiving a frusto-conical nozzle 6 having an upwardly presented seat or orifice l and a downwardly presented diametral slot or nick 8 for facilitating nozzle-adjustment.

Welded or otherwise fixed upon the outer or under face of the end plate 4 in registration with the aperture 5, is a'connection collar 9 for conventional hermetically sealed engagement with I the connection flange Ill of asupply line" I I, all as best seen in Figures 1 and 3 and for purposes presently more fully appearing.

Welded or otherwise fixed upon the innerface of the shell I "a short-distance downwardly from the upper margin thereof, is an annular series of suitably spaced blocks I 2 for supporting engagement with an annular plate I3 having an external diametral size substantially equivalent to that of the shell I and forming with the shell I an enclosed sump chamber a, the plate I3 being of suflicient thickness to project a substantial distance above the upper margin of the shell I, all as best seen in Figure 1 and for purposes more fully presently appearing.

Adjacent its periphery, the plate I3 is apertured, as at I4, and centrally on its under face has 'a shallow annular recess, as at I5, of relatively large diameter, as shown. The plate I3 also hasacentral valve stem accommodating aperture I6, while surrounding the recess I5, the plate I3 has an'annular seriesof stud accommodating apertures I1, all as'best seen in Figures 1 and 3, and for purposes presently fully appearing.

' Disposed 0n the under face of the plate I3, is a diaphragm I 8; which extends over the recess 15 in the formation of an actuating or pressure chamber :b, the diaphragm I8 having'a plurality of apertures I9 in registration with the apertures I1 and a central aperture 26 substantially larger and in axial alignment with the aperture I6.

Disposedqupon the under face of,xand in peripheral registration with, the diaphragm I8,'is a sealing ring 2| having a plurality of internally threaded recesses 22 in registration with the apertures II, I9, for receiving stud-bolts 23,.which latter extend through the apertures I'l, I9, into the recesses-22 and draw thering 2I toward the plate I3 for tightly sealing the diaphragm I8 therebetween.

Formed integrally with, and suspended from, the sealing ring 2|, is a frusto-conical or cupped plate 24 centrally provided with a valve stem accommodating guide aperture 25 in registering alignment with the base aperture I 6, the plate 24 being also provided in the wall of theaperture with an annular series of slots, as at 26, opening to the opposite faces of the plate M for providing free or open communication between the chamber a and the underside of the diaphragm I3.

Mounted concentrically within the recess I5 upon the upper face of the diaphragm I8, is an upper pressure plate 21 having a concentric hub 28 sized to snugly fit the enlarged diaphragm aperture for engagement with a second or lower pressure plate 30 mounted on the under face of the diaphragm I8 in concentric alignment with the upper pressure plate 21, the bore of the hub 28 being in registration with the aperture I6 of the plate I3 and the pressure plate providing an abutment for the upper end of a compression spring 3| impingingly seated at its other end in an annular channel 32 in the cuplike member 24, all as best seen in Figure 1 and for purposes presently appearing.

The shell I is preferably provided with an out-' let aperture 33 and an external registering connection collar 34 for conventional engagement with the flanged end 35 of the outlet line 35, all as best seen in Figure 1 and for purposes presently more fully appearing.

Welded or otherwise fixed, as at 29, upon the under face of the cup-like member 24, is an elbow tube 31 terminating at its upper end in substantially'flush alignment with an outlet aperture 33 formed in the shell I and at its other end in a plane spaced a short distance above the orifice I, the tube 31 in its lower end portion being provided with an annular insert-sleeve 39 internally bored in the provision of a Venturi-constriction 40.

In its side wall, the tube 31 is provided with a valve stem accommodating aperture 4| also in registering alignment with the valve stem accommodating aperture I6 of the plate !3, all as best seen in Figure 1 and for purposes presently appearing.

Welded or otherwise fixed in the hub 28 for shiftable movement with the pressure plate 21, is a tubular valve stem 42 extending upwardly through the recess I5 and shiftably' through the aperture I5 of the plate I3 and downwardly through the aperture 25 of the plate 24 and the aperture 4| of the elbow tube 31 and axially through the Venturi-constriction 40 and orifice I, the stem 42 bein provided on its lower end with an annular nozzle engaging ring 43.

The stem 42 is further provided with two longitudinally spaced pairs of diametrally opposed apertures 44, 45, disposed on respectively opposite sides of the base plate I3.. Fixed within the stem 42 and spaced downwardly from the lowermost pair of apertures 44, i an annular seatforming collar 46 for accommodating the reduced end of a valve-pin 41 shiftably mounted in, and projecting at its upper extremity outwardly from the upper end of, the valve stem 42.

Fixed above the uppermost pair of apertures upon, and extending obliquely across, the upper end of the'valve stem 42, is a fulcrum plate 48 having an upwardly presented acumi nate or knife-edge 49 spaced laterally a short distance from the axial center line of the valvepin 41, all as best seen in Figure 1 and for purposes presently more fully appearing.

Welded or otherwise fixed upon the upper face of the plate I3 adjacent its outer periphery, is an upwardly extending channel-shaped support member 59 provided at its extremity with a pivot or hinge pin 5I, swingably mounted upon which is a pair of links 52 arcuated or bowed outwardly and brought together at their outer ends for pivotal connection with a pin 53 mounted at its ends in and extending between a pair of short inwardly projectin ears 54 welded or otherwise fixed upon the inner face of a suitable catchbucket 55 provided in its side wall with a drain aperture '55 so positioned and sized as to permit the liquid contents of the bucket 55 to drain therefrom at a predetermined rate.

On its under face, the bucket 55 is provided with a pair of laterally spaced downwardly projecting ears 5? for pivotal connection with the outer end of a counterbalancing lever 58, which, at its inner end, rests upon the upper end of the valve-pin 41 and the knife-edge 49 of the fulcrum plate 48.

Riveted or otherwise fixed on, and extending as a continuation beyond the inner end of, the lever 58, is a counterbalancing leaf sp 59 deflec e downwardly at its free end and adjustably held in such deflected position between a pair of clamp nuts B l, 6|, threadedly disposed upon a vertical stud 62, which is, in turn, mounted at its lower end in the plate I3.

Adjacent its upper margin and opposite the supporting member 55 the cup 55 is cut away in the formation of a U-shaped clearance slot 63 in a more or less conventional manner, sothat the cup 55 will not strike against the supporting links 52 and interfere with its own free swinging vertical movement, all as best seen in Figures 1 and 2 and for purposes more fully appearing.

Mounted in snug fitting annular engagement around the upwardly projecting portion of the base plate I3 and registering endwise with the shell I, is a cylindrical cap 54 provided at or adjacent its lower margin with an external annular flange 55 machined for complementary seating engagement with the shell flange 2 and having a plurality of apertures, as at 56, for accommodating attachment bolts 61 threadedly engaging the flange 2 at the apertures 3 for drawing the cap 64 and shell I into tight hermetically sealed engagement. "As also seen in Figure 1, the cap 64 is further provided at its upper end with a rounded or dome-shaped end wall 68 centrally provided with an aperture 69.

Welded or otherwise fixed in hermetically sealed relationship upon the upper face of the end wall 68 in registration with the aperture 69, is a preferably conical connection fitting I0 provided upon its inclined faces with a pair of more or less diametrally opposed apertures II, I2, for communication, respectively, with conventionally mounted return and suction lines I3 and i4.

Welded or otherwise fixed in the aperture I2 of, and extending axially downwardly and inwardly from, the fitting i0, is a thin-walled tube 15 diametrally enlarged and presented downwardly in the provision of an inner cylindrical baiile I6 disposed concentrically-within the cap 54 and downwardly into the catch-bucket 55. Similarly welded or otherwise fixed to and upon the under face of the end wall 68 of the cap 64 in marginal registration with the aperture 69, is an outer cylindrical baifle I8 also extending concentrically downwardly into the interior of the cap 64 and terminating inside of the catchbucket 55 in a plane preferably spaced slightly upwardly from the plane of the lower margin of the inner bafile wall 16.

It will be noted by reference to Figures 1 and 2 that the inner bafile I5 and its associated tube I5 are substantially smaller in diametral size than the outer ballie I8, so as to provide an outer chamber I9 having communication with the return line I3 and an inner chamber having communication with the suction line I4.

upwardly through :the bafflelli and tube -into .the suction line "14, from which it returns -tothe Mounted "at their ends upon, and extending radially between-the bafiies 16 and i8, and positioned preferably adjacent the lower extremity of the bafile 13, is a series of downwardly deflected vanes 8|, all as best seen in Figures 1 and 2 and for purposes presently fully appearing.

Although the control valve of my present invention may be employed in a wide variety of different systems employing liquids under pressure, .the valve A is, for purposes of explanation, here shown in connection with a more or less conventional type of refrigerating system which includes a compressor B connected to a liquid receiver C, in turn, connected to the intake or Connected at its intake-end to supply line I I. an outlet line 36, is a conventional coil-type evaporator D serving as the point of application, so to speak, of the fluid flow being consubstantially empty. Meanwhilethe high pressure of the liquid refrigerant in the intake line I i will be exerted through the tube-like valve stem 42 against the valve-pin t'l. This pressure, in combination with the counterbalancing tension of the leaf spring 59, will force the bucket. 55 upwardly and permit the pin 4'1! to move out of seating engagement with the seat-forming collar 46. Thereupon a small quantity of liquid refrigerant will expand through the apertures M into the chamber b, forcing the diaphragm I8 downwardly and compressing the spring 3!. Accordingly, the entire valve stem 42 will be shifted downwardly and the valve ring 43 moved out of seating engagement with the nozzle thereby allowing the high pressure liquid refrigerant of the intake H to expand :and flow through the orifice l and the Venturieconstriction into the elbow tubeiiland thencethrough the outlet pipe 35 to the-evaporator D.

In the evaporator, the liquid refrigerant will expand, so that'the fluid returning from the discharge side of the evaporator through the-return line 73 will be partially liquid and -.partially,;gas

and will, upon enteringthe annular chamber 19, impinge against the inclined walls of the .tube 15 and take up a tangential motion, centrifugally separating the major portion of the liquid from the gas. As the gas fiows downwardlyacross' the vanesSi, a final rotatory motion thereby =imparted to it will effect separation and removal of the remaining liquid. I

The returned liquid will drain downwardly over the side faces of the baffles 3 78 and the vanes SI and into the catch-bucketfit. Then, as the level of the returned liquid in' the-bucket 55 rises above the aperture 5%, the liquid will commence to flow out of the bucket at apredetermined rate and fall through the aperture &4 of the plate It into the lower portion .of the chamber-a, from which it will be drawn'by'the suction of the Venturi-constriction 55 back into the elbow tube 3? for recirculating with the incoming supply of liquid.

At the same time, liquid free gaseous refrigerant meanwhile reverses its direction'and flows compressor B for recompression.

As :soon as the evaporator temperature becomes sufficiently lowered, the ratio'between the quantities of refrigerant which return in liquid and gaseous phases, respectively, will increase,

so that a' materially larger quantity of liquid-refrigerant 'will "flow into the catch-bucket 55.

-Since "the rate of efiluxufrom the bucket .through the aperture '56 is relatively constant,

the weight of the bucket 55 will increase until the increase is sufiicient to overcome the force of the counterbalancing'spring 59. Thereupon, the

.counterbalancingarm' 53 will swing downwardly,

shifting the valve 47 into closer seated position, restricting the'supply of high pressure evaporating refrigerant which has been entering the 'chamber'b through the apertures Mto hold the diaphragm 1'8 in downwardly disposed position against the spring 3|. As this supply of refrigerant is restricted or entirely-cutoff, asthe case may be, the gas in the chamber 12 will leak past :theannular clearance between the aperture 216 of the plate l3 and the outerface'of the valve :stem 42, thus reducing the pressure in the chamber bandallowing the spring 3| to shift the diaphragm18 and the valve stem 42 upwardly for restricting or cutting off the influx of liquid-refrigerant through the orifice l. The apertures i 35 serveto vent fthe'long seating fit of the valve :pin ill and facilitate eliicient pilot action.

If desired, the chamberb may be provided with an adjustable leak port p of conventional design, as shown'in Figure 5,*in.which case the annular leakage clearance between the aperture I6 and the valve-stem 52 may be dispensed with.

In this connection, it should be noted that the fulcrum plate 48 is mounted directly on the valve stem 42 and accordingly shifts upwardly and downwardly upon opening and closing movements of the stem 42 relatively to the nozzle 5. It will also beznoted that, as the-fulcrum plate 48 and the knife-edge '45 thereof move downwardly, the tension creating deflection of the spring 59 is decreased, thereby reducing the amount of compcnsating force exerted thereby.

This has the same effect as an increase in the weight of the bucket 55. Consequently, as the valve stem'4l2 is shifted to open the nozzle 6, the

knife-edge 59 is lowered to a certain degree, thereby'making the weight of the bucket 55 moi mentarily more effective, so as to urge the valvepin 4'! downwardly, restricting the actuating pressure exerted inthe chamber b and permitting the spring 3| to shift the valve stem 42 upwardly again toward closure position to restrict somewhat, or under extreme circumstances even entirely cut off, the in'iiowing liquid refrigerant from the supply line.

This produces automatic compensating effect, which prevents so-called wild hunting or cycling which normally results from over-travel of the control valve. As will be understood, cycling-or wild hunting is particularly serious in refrigerating systems where the evaporator is relatively long or'large and, in fact, frequently becomes so serious as to destroy all possibility of accurate control.

In valves constructed in accordance with my invention, however, the automatic compensation which results from the shifting movement of the fulcrum 48 accurately anticipates the required degree of control long before the liquid refrigerant whichshas entered the evaporator in response to a particular control position has returned to the control valve and made itself directly effective sponsive flow control of the type more particularly shown in my co-pending application Serial No. 280,720 may be substituted for the drip bucket 55, if desired.

It will also be noted that all of the moving parts of the valve are uniquely assembled upon the single base plate l3,.so that the entire operating structure may be assembled in a series of convenient bench operations and bodily installed within the shell I and cap 64. Not only does this make possible material economy in the initial production and manufacture of the valve, but also makes it possible to repair the valve quickly and conveniently.

As has been above stated, control valves of my present invention are applicable to a wide variety of uses, such as steam boiler control, air pressure regulation in humidification apparatus, liquidvapor phase control in oil distillation apparatus and other types of fractionating or distilling columns, as well as to refrigerating systems. Regardless of application or use, it will be evident that, by my present invention, I provide a unique control valve which is capable of serving as a flow rate metering device, thereby securing extremely high efficiency in the apparatus controlled. The control valve of my present invention furthermore serves to recirculate the unevaporated liquid which leaves the evaporator or other apparatus at the discharge side. In addition, the valve functions to separate the liquid gaseous components of the liquid discharged from the evaporator or other apparatus in an unusually efficient and satisfactory manner. Finally, valves of my invention are operated upon a relay or servo-motor principle and are automatically compensated for over-travel.

It should be understood that changes and modifications in the form, construction, arrangement, and combination of the several parts of the valve may be made and substituted for those hereinshown and described without departing from the nature and principle of my invention.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

l. A valve adapted to control the flow of a supply of vaporizable liquid responsive to the rate of return of unevaporated liquid comprising a shell having a chamber, said shell having a pair of apertures opening into the chamber for passing the return flow through the chamber, first means operatively mounted in the chamber actuable responsive to variations in rate of return flow of unevaporated liquid, valve means for controlling flow of supply liquid, and means connecting the valve means with the first means for actuation thereby.

2. A valve adapted to control the flow of a supply of vaporizable liquid to a device responsive to the rate of return of unevaporated liquid from such a device comprising a shell having upper and lower chambers, said shell having a pair of apertures opening into the upper chamber for passing the return flow through the upper chamher, a catch bucket operatively mounted in the upper chamber, means for conducting a flow of supply liquid through the lower chamber, valve means for controlling flow of supply liquid, and means connecting the valve means with the catch bucket for actuation thereby.

3. A valve adapted to control the flow of a supply of vaporizable liquid to a device responsive to the rate of return of unevaporatedliquid from such a device comprising a shell, a transverse member interiorly dividing the shell into upper and lower chambers, means for passing the return flow through the upper chamber, a catch bucket operatively mounted on the transverse member for actuation responsive to change in the rate of return flow of unevaporated liquid, means for conducting a flow of supply liquid through the lower chamber, valve means for controlling flow of supply liquid-and means connecting the valve means with the catch bucket for actuation thereby.

4. A valve adapted to control the flow of a supply of vaporizable liquid responsive to the rate of return of unevaporated liquid comprising a shell, a transverse member interiorly dividing the shell into upper and lower chambers, means for passing the return flow through the upper chamber for separation of any entrained liquid, a catch bucket operatively mounted on the transverse member for actuation responsive to change in the rate of return flow of entrained liquid, said bucket having an aperture to permit efilux of the return flow liquid caught therein and said transverse member being provided with an aperture for permitting the efflux liquid from the bucket to drain into the lower chamber, conduit means for conducting a flow of supply liquid through the lower chamber, valve means for controlling flow of supply liquid, means connecting the valve means with the catch bucket for actuation thereby, and means associated with the conduit means and communicating with the lower chamber for introducing the efilux liquid into the flow of supply liquid for recirculation.

5. A valve adapted to control the flow of supply liquid responsive to rate of flow of return liquid comprising a shell, a transverse member interiorly dividing the shell into upper and lower chambers and having an aperture for providing communication between said chambers, the shell having a pair of apertures opening into the upper chamber for passing the return flow through said upper chamber, means in the upper chamher for separating entrained liquid from the return flow, a catch bucket operatively mounted on the transverse member for receiving the separated liquid and being apertured for permitting the liquid to flow at a predetermined rate into the lower chamber through the aperture in the transverse member, means for conducting the flow of supply liquid through the lower chamber, valve means for controlling liquid flow through the lower chamber, and means connecting the valve means with the catch bucket for actuation thereby.

6. A valve adapted to control a supply flow of vaporizable liquid responsive to the rate of flow of unevaporated liquid comprising a shell, a transverse member interiorly dividing the shell into upper and lower chambers and having an aperture for providing communication between said chambers, the upper chamber having an intake port for receiving the return flow, separator means in the upper chamber for removing entrained liquid from the return flow, said upper chamber further having an outlet port 'for discharging the vaporized portions of the return flow, a catch bucket operatively mounted'on the transverse member for receiving the separated return liquid, said catch bucket being apertured for maintaining a normal liquid-level therein and permitting any liquid in excess of such normal liquid-level to flow onto the transverse member and through the aperture thereof into the lower chamber, means for conducting a flow of supply liquid through the lower chamber, valve means for controlling the flow of supply liquid, means connecting the valve means with the catch bucket for actuation thereby, and means in the lower chamber for introducing the return liquid into the flow of supply liquid.

7. In a device of the character described, a valve having a shiftable valve stem, pressureactuated operating means for shifting the valve stem, means for imposing pressure on the operating means, movable actuating means for varying the pressure imposed on the operating means, and means carried by the valve stem for modifying the effective movement of the actuating means for limiting travel of the valve stem to substantially prevent false-positioning thereof.

8. In a return flow responsive valve of the character described, a shiftable valve stem, actuating means operably connected to the valve stem for opening and closing the valve, an auxiliary valve for controlling the operation of the actuating means, control means operably mounted for shiftable movement responsive to variations in the rate of return flow, a lever fulcrumed on the valve stem for transmitting movement of the control means to the auxiliary valve, and a counterbalancing leaf spring associated with the lever and adapted normally to oppose the effect of the control means upon the auxiliary valve.

9. In a return flow responsive valve of the character described, a shiftable valve stem, actuating means operably connected to the valve stem for opening and closing the valve, an auxiliary valve for controlling the operation of the actuating means, control means operably mounted for shiftable movement responsive to variations in the rate of return flow, a lever fulcrumed on the valve stem for transmitting movement of the control means to the auxiliary valve, and a counterbalancing leaf spring associated with the lever and adapted normally to oppose the effect of the control means upon the auxiliary valve, said spring being adapted to have reduced opposing effect as the fulcrum moves with the valve stem for compensating over-travel of said stem.

10. In a return flow responsive valve of the character described, a shiftable valve stem, actuating means operably connected to the valve stem for opening and closing the valve, an auxiliary valve for controlling the operation of the actuating means, control means operably mounted for shiftable movement responsive to variations in the rate of return flow, a lever operably connected to the auxiliary valve for transmitting movement of the control means to the auxiliary valve, said lever having a leaf spring extending outwardly from an end thereof for exerting upon the lever, a force in opposition to the movement of the control means and means shiftable responsive to movement of the valve stem for modifying the opposing force of the spring as the valve opens.

11. In a fluid flow controlling valve, a body having a main chamber and an auxiliary chamber, a shiftable diaphragm separating said chambers, means connected to the diaphragm for controlling the flow of fluid through the valve, means for by-passing aportion of the fluid from the high-pressure sid of the valve to the auxiliary chamber'for actuating the diaphragm, and means for controlling'the flow of diaphragm-actuating fluid into the auxiliary chamber for actuating the diaphragm-to increase-or decrease the flow of fluid through the valve responsive to an external demand.

12. In a fluidflow controlling valve, a body having a main chamber and an auxiliary chamber, a shiftable diaphragm separating said chambers, aseat-forming nozzle for introducing fluid into the main chamber, a fluid discharge conduit leading from the main chamber, a shiftable plug inter-posed between the nozzle and conduit for controlling the flow of fluid-from the nozzle to the conduit, a tubular stem extending at one end through the plug into the interior of the nozzle and at its other end being fixed in and extending through the diaphragm for communication with the-auxiliary chamber for conducting highpressure fluid directly from the nozzle to the auxiliar chamber for actuation of the diaphragm, and means associated with the stem for controlling the flow of high-pressure fluid to the auxiliary chamber.

-13.-A valve adapted to control the flow of I a supply of vaporizable liquid to a device responsive to the rate of return of unevaporated liquid from such a device comprising a shell having upper and lower chambers, said shell having a pair of apertures opening into the upper chamber for passing the return flow through the upper chamber, liquid-flow measuring means operatively mounted in the upper chamber, means for conducting a flow of supply liquid through the lower chamber, valve means for controlling flow of supply liquid, and means connecting the valve means with the liquid-flow measuring means for actuation thereby.

14. A valve structure comprising a body providing a chamber, a first inlet, a first outlet, movable throttling means for controlling the flow of liquor from said inlet to said outlet, a second inlet for introducing a mixed stream of liquid and vapor into said chamber, means in the chamber actuable in response to changes in liquid content in th stream for operating said throttling means to control the flow of liquid from th first inlet to the first outlet, and a second outlet for the vapor component of said stream.

15. A valve structure comprising a body providing a chamber, a first inlet, a first outlet, movable throttling means for controlling the flow of liquid from said inlet to said outlet, a second inlet for introducing a mixed stream of liquid and vapor into said chamber, means in the chamber actuable in response to fluctuations in the quantity of the liquid component of said stream for operating said throttling means to control the flow of liquid from the first inlet to the first outlet, a second outlet for the vapor component of said stream, and means for recirculating a portion of said liquid component with the liquid flowing from the first inlet to the first outlet.

16. A valve structure comprising a body providing a chamber, a first inlet, a first outlet, movable throttling means for controlling the flow of liquid from said inlet to said outlet, a second inlet for introducing a mixed stream of liquid and vapor into said chamber, means in the chamber actuable in response to fluctuations in the quantity of the liquid component of said stream for operating said throttling means to control th flow of liquid from the first inlet to the first outlet, a second outlet for the vapor component of said stream, and means for injecting a portion of the liquid component into the liquid flowing from the first inlet to the first outlet.

17. A valve structure comprising a body providing a chamber, a first inlet, a first outlet, movable throttling means for controlling the flow of liquid from said inlet to said outlet, a second inlet for introducing a mixed stream of liquid and vapor into said chamber, means in the chamber actuable in response to changes in liquid content in the stream for operating said throttling means to control the flow of liquid from the first inlet to th first outlet, a second outlet for the vapor component of said stream, and means for damping the movement of the throttling means.

18. A valve structure comprising a body providing a chamber, a first inlet, a first outlet, movable throttling means for controlling the fiow of liquid from said inlet to said outlet, a second inlet for introducing a mixed stream of liquid and vapor into said chamber, servo-motor means in the chamber actuable in response to changes in liquid content in the stream for operating said throttling means to control theflow of liquid from th first inlet to the first outlet, and a second outlet for the vapor component of said stream.

19. A valve structure comprising a body providing a chamber, a first inlet, a first outlet, movable throttling means for controlling the fiow of liquid from said inlet to said outlet, a second inlet for introducing a mixed stream of liquid and vapor into said chamber, means in the chamber actuable in response to changes in liquid content in the stream for operating said throttling means to control the flow of liquid from the first inlet to the first outlet, a second outlet for the vapor component of said stream, and means for damping the movement of the servo-motor means to substantially overcome hunting.

20. A refrigerating system including, a compressor, a condenser, an evaporator, a supply line connecting the evaporator and condenser, a return line connected to the evaporator and compressor for conducting a, mixed stream of liquid and vapor from said evaporator to said compressor and a flow controlling device interposed in both the supply and return lines, said device including a chamber, movable throttling means in the chamber for controlling the liquid fiow through the supply line, means also in the chamber for removing the liquid component of said mixed stream and conducting said liquid component into the chamber, and means movable responsive to changes in the quantity of said liquid component fiowing into the chamber for operating the throttling means.

21. A refrigerating system including, a compressor, a condenser, an evaporator, a supply line connecting the evaporator and condenser, a return line connected to the evaporator and compressor for conducting a mixed stream of liquid and vapor from said evaporator to said compressor and a flow controlling device interposed in both the supply and return lines, said device including a chamber, movable throttling means in the chamber for controlling the liquid flow through the supply line, means also in the chamber for removing the liquid component of said mixed stream and conducting said liquid com ponent into the chamber, means movable responsive to changes in the quantity of said liquid component flowing into the chamber for operating the throttling means, and means for recirculating a portion of said liquid component with the liquid fiowing in the supply line.

22. A refrigerating system including, a compressor, a, condenser, an evaporator, a supply line connecting the evaporator and condenser, a return line connected to the evaporator and compressor for conducting a mixed stream of liquid and vapor from said evaporator to said compressor and a flow controlling device interposed in both the supply and return lines, said device including a chamber, movable throttling means in the chamber for controlling the liquid flow through the supply line, means also in the chamber for removing the liquid component of said mixed stream and conducting said liquid component into the chamber, means movable responsive to changes in the quantity of said liquid component flowing into the chamber for operating the throttling means, and means for injecting a portion of the liquid component into the supply line.

23. A refrigerating system including, a compressor, a condenser, an evaporator, a supply line connecting the evaporator and condenser, a return line connected to the evaporator and compressor for conducting a mixed stream of liquid and vapor from said evaporator to said compressor and a flow controlling device interposed in both the supply and return lines, said device including a chamber, movable throttling means in the chamber for controlling the liquid flow through the supply line, means also in the chamber for removing the liquid component of said mixed stream and conducting said liquid component into the chamber, means movable responsive to changes in the quantity of said liquid component flowing into the chamber for operating the throttling means, and means for damping the movement of the throttling means.

24. A refrigerating system including, a compressor, a condenser, an evaporator, a supply line connecting the evaporator and condenser, a return line connected to the evaporator and compressor for conducting a mixed stream of liquid and vapor from said evaporator to said compressor and a flow controlling device interposed in both the supply and return lines, said device including a chamber, movable throttling means in the chamber for controlling the liquid flow through the supply line, means also in the chamber for removing the liquid component of said mixed stream and conducting said liquid component into the chamber, and servo-motor means actuable to changes in the quantity of said liquid component flowing into the chamber for operating the throttling means.

PARKE H. THOMPSON. 

